Atomic-resolution characterization of the effects of CdCl{sub 2} treatment on poly-crystalline CdTe thin films

Journal Article · Mon Aug 18 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4893727· OSTI ID:22310877

Buurma, C.; Colegrove, E.; Guo, Z.; Sivananthan, S.; Klie, R. F. ^[1]; Chan, M. K. Y. ^[2]

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1. Department of Physics, University of Illinois at Chicago, 845 W. Taylor St. M/C 273, Chicago, Illinois 60607-7059 (United States)
2. Center for Nanoscale Materials, Argonne National Laboratory, 9700 S. Cass Ave., Building 440, Argonne, Illinois 60439 (United States)

Poly-crystalline CdTe thin films on glass are used in commercial solar-cell superstrate devices. It is well known that post-deposition annealing of the CdTe thin films in a CdCl{sub 2} environment significantly increases the device performance, but a fundamental understanding of the effects of such annealing has not been achieved. In this Letter, we report a change in the stoichiometry across twin boundaries in CdTe and propose that native point defects alone cannot account for this variation. Upon annealing in CdCl{sub 2}, we find that the stoichiometry is restored. Our experimental measurements using atomic-resolution high-angle annular dark field imaging, electron energy-loss spectroscopy, and energy dispersive X-ray spectroscopy in a scanning transmission electron microscope are supported by first-principles density functional theory calculations.

• OSTI ID: 22310877
• Journal Information: Applied Physics Letters, Vol. 105, Issue 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANNEALING
CADMIUM CHLORIDES
CADMIUM TELLURIDES
COMPUTERIZED SIMULATION
DENSITY FUNCTIONAL METHOD
DEPOSITION
ELECTRONS
ENERGY-LOSS SPECTROSCOPY
GLASS
POINT DEFECTS
RESOLUTION
SOLAR CELLS
STOICHIOMETRY
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY SPECTROSCOPY